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Dear Patrick and All,</div>
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Thank you for pointing this out. In fact, both denominations "virtual photon flux" and "virtual photon equivalent energy" are routinely used for
<i>K</i>. For example, the textbook of R. G. Roberts "<i>The structure of the proton</i>" uses "flux", while the Thomas-Weise textbook "<i>The structure on the nucleon</i>" uses "equivalent energy". </div>
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We have thus modified this part of the manuscriot, which now reads:</div>
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"<span style="color: rgb(200, 38, 19);">The virtual photon equivalent energy <i>K</i> (sometimes called virtual photon flux)<br>
in Eqs. (8-9)</span>"</div>
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I hope this adequately takes care of the issue. Please let me know if not.</div>
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Best regards,</div>
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Alexandre, also for Marco, Xiaochao and Sebastian</div>
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<div id="divRplyFwdMsg" dir="ltr"><span style="font-family: Calibri, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);"><b>From:</b> Patrick Achenbach <patricka@jlab.org><br>
<b>Sent:</b> Wednesday, June 12, 2024 07:40 PM<br>
<b>To:</b> clasmbr@jlab.org <clasmbr@jlab.org>; clascomment@jlab.org <clascomment@jlab.org>; William Phelps <wphelps@jlab.org>; briscoe@gwu.edu <briscoe@gwu.edu>; Volker Burkert <burkert@jlab.org>; skuhn@odu.edu <skuhn@odu.edu>; Marco.Ripani@ge.infn.it <Marco.Ripani@ge.infn.it>;
Xiaochao Zheng <xiaochao@jlab.org>; Alexandre Deur <deurpam@jlab.org>; benmokhtarf@duq.edu <benmokhtarf@duq.edu><br>
<b>Subject:</b> OPT-IN: Measurement of the nucleon spin structure functions for 0.01 < Q2 < 1 GeV2 using CLAS</span>
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<div style="font-size: 11pt;">After a very short glimpse at the paper:<br>
"The virtual photon flux K in Eqs. (8-9)..." This variable is indeed not observable, so it's naming is not very relevant, but it is better called an energy, e.g. virtual photon energy or photon equivalent energy.</div>
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